1. Field of Use
This invention relates generally to vaccines for veterinary use. In particular, it relates to Chlamydia vaccines useful for prevention and treatment of disease processes created or induced by Chlamydia organisms in mammalians other than felines, particularly those of the bovine species, and to methods for immunizing and treating such animals with such vaccines.
2. Description of the Prior Art
Various strains of the Chlamydia psittaci organism (psittacosis-lymphogranuloma group) have been reported frequently as involved in various mammalian and avian disease processes. The pathology described includes the following disease processes: enzootic abortion in ewes, epizootic bovine abortion, feline pneumonitis, psittacosis-ornithosis, sporadic bovine encephalomyelitis, transmissible serositis in sheep, calves and swine, bovine respiratory disease complexes, enzootic pneumonia in calves, neonatal diarrhea of calves, polyarthritis in sheep and others.
The "Merck Veterinary Manual", Fourth Edition, published by Merck & Co., Inc. of Rahway, N.J., U.S.A. (1973) provides specific descriptions of the aforementioned and other related pathologies, the occurrence of Chlamydial organisms in connection therewith, the recommended forms of treatment, and the chemotherapeutical agents known and recommended for use therewith, especially at pages 166, 272, 274, 277, 322, 375, 385 and 879, as well as elsewhere.
The following references designated numbers 1 through 16 provide further information about such diseases and their treatment.
1. Boidin, A. G., Cordy, D. R., and Adler, H. E.: A Pleuropneumonia-like Organism and a Virus in Ovine Pneumonia in California. Cornell Vet., 48, (1959): 410-430.
2. Edward, A. G., Mills, G. D., and Calhoon, J. R.: Production of Colostrum-Deprived Specific Pathogen-Free Calves. Lab. Anim. Care, 17, (1967): 103-109.
3. Eugster, A. K., and Storz, J.: Pathogenetic Events in Intestinal Chlamydial Infections Leading to Polyarthritis in Calves. J. Infect. Dis., 123, (1971): 41-50.
4. Gimenez, D. F.: Staining Rickettsiae in Yolk-Sac Cultures. Stain Technol., 39, (1964): 135-140.
5. Kawakami, Y., Omori, T., Fukuhara, S., Tokuda, G., Ishii, S., and Matumoto, M.: Studies on the Disease of Cattle Caused by a Psittacosis-Lymphogranuloma Group Virus (Miyagawanella). VII. Isolation of a Virus, Identified as a Member of the Psittacosis-Lymphogranuloma Group of Viruses, from Feces of Cattle. Jap. J. Exptl. Med., 25, (1955): 51-63.
6. Page, L. A.: Proposal for the Recognition of Two Species in the Genus Chlamydia Jones, Rake and Stearns, 1945. Internat. J. Sys. Bact., 18, (1968): 51-66.
7. Reed, C. J., and Muench, M.: A Simple Method for Estimation of Fifty Percent Endpoints. Am. J. Hyg., 27, (1938): 493-497.
8. Smith, P. C., Cutlip, R. C., and Page, L. A.: Pathogenicity of a Strain of Chlamydia psittaci of Bovine Intestinal Origin for Neonatal Calves. Am. J. Vet. Res., 34, (May, 1973): In press.
9. Storz, J., Collier, J. R., Eugster, A. K., and Altera, K. P.: Intestinal Bacterial Changes in Chlamydia-induced Primary Enteritis of Newborn Calves. Ann. New York Acad. Sci., 176, (1971): 162-175.
10. Storz, J., Eugster, A. K., Altera, K. P., and Olander, H. J.: Behavior of Different Bovine Chlamydial Agents in Newborn Calves. J. Comp. Path. & Therap., 81, (1971): 299-307.
11. Storz, J., Marriott, M. E., and Winterer, B. I.: Detection and Separation of Simultaneous Enterovirus and Intestinal Chlamydial Infection of Calves. Zentralbl. Bakt. (Orig.), 210, (1969): 75-81.
12. York, C. J., and Baker, J. A. A New Member of the Psittacosis-Lymphogranuloma Group of Viruses that Causes Infection in Calves. J. Exptl. Med., 93, (1951): 587-604.
13. York, C. J., and Baker, J. A.: Miyagawanella bovis Infection in Calves. Ann. New York Acad. Sci., 66, (1956): 210-214.
14. Journal of the South African Vet Association (1977), Vol. 48, p. 261. It mentions that "abortions in sheep and cattle is well controlled by vaccination, but as yet no effective vaccine for the protection of the newborn has been developed".
15. Deutsche Tieranztlicke Wochenschrift (1975), Vol. 82, pp. 221 It states that two inactivated vaccines--"were tested on 16,581 sheep. The effectiveness of immediate vaccination of pregnant, including aborting animals, was therefore proved for both vaccines".
16. Journal of the AVMA (1974), Vol. 165, No. 8, pp. 689 It describes the use (or refers to the use) of an inactivated vaccine.
Heretofore, the above-referred to disease processes have been treated in a conventional manner by means of chemotherapeutic agents, with particular success experienced by the use of high levels of tetracyclines orally or intravenously administered over prolonged periods of time. However, insofar as applicant is aware, there is no known vaccine which is commercially available for the prevention or treatment of these disease processes in any species of animal, other than in felines and particularly, there is no teaching or recommendation to use live or modified live vaccine in bovines.
An example of a commercially available vaccine for immunization against and prevention of feline pneumonitis is Feline Pneumonitis Vaccine, Modified Live Chlamydia-Chicken Embryo Origin (trade name PSITTACOID) produced for veterinary use only under U.S. Veterinary License No. 195-A for immunization of cats against Chlamydia psittaci by Fromm Laboratories, Inc., Grafton, Wisc. 53024, U.S.A. The recommended dosage and administration for cats is as follows: Rehydrate each 1 cc vial of vaccine with 1 cc of diluent and inject intramuscularly or subcutaneously. Vaccinate healthy cats of any age with one dose except that if the animal is less than 12 weeks of age a second dose should be given at 12 to 16 weeks of age. Annual revaccination with a single dose is recommended. Each 1 cc vial of vaccine contains the vaccine in desiccated form containing 10.sup.5.1 (at least 100,000 plus) modified live organisms which is to be diluted with a sterile diluent such as distilled water.
The aforementioned conventional treatment of bovines, for example, suffering from Chlamydial infections by means of chemotherapeutical agents is generally satisfactory, but has the drawbacks of being relatively time-consuming, expensive, and lacking long-term effectiveness. For example, the conventional treatment of an individual animal typically involves administration of recommended dosages of tetracyclines over a period of five or more consecutive days followed by subsequent observations at less frequent intervals to ascertain treatment effectiveness. Furthermore, a successfully treated individual animal remains a carrier of the disease organism and is itself susceptible to reoccurrence of the disease, as well as being a source of infection to other animals in the herd. Such treatment, therefore, is costly from the standpoint of veterinary services required and as regards the type and quantity of medication.
While the foregoing factors generally point to the desirability of discovering a more economical and effective control regime for Chlamydial infections in agricultural animals, particularly of those of the bovine species, none has heretofore been forthcoming for a variety of reasons. For example, historical experience and classical theory in the science and practice of veterinary medicine indicates that immunizing agents and methods of treatment involving the same may be successfully employed with one species of animal but are not necessarily effective, safe, or even available for another species. Indeed, not infrequently, whereas beneficial results may occur in one species, unpredictable detrimental results can and often do occur in others. This fact has led to the development of different points of view and schools of thought within the profession regarding the desirability and possible effectiveness of using specific agents on different species. Furthermore, it is very often not possible to perform any studies, experiments or tests to establish effectiveness or non-effectiveness, especially those involving large numbers beef or dairy cattle, nimals such as where the possibility of risk or failure may not only be costly and inconclusive, but totally disastrous.